(a) Field of the Invention
The invention relates to a light diffraction member and a display and a backlight module having the light diffraction member.
(b) Description of the Related Art
FIG. 1 shows an explosion diagram illustrating a conventional display 10. Referring to FIG. 1, the display 10 includes a display panel 11 and a backlight module 20. The backlight module 20 includes a back plate 21 and a light guide plate 22, a reflective sheet 23, a light source 24 and an optical film set. The optical film set includes a diffusion plate 25, a first brightness enhancement film 26, and a second brightness enhancement film 27. The diffusion plate 25 is adjacent to the light emitting side of the light guide plate 22. The reflective sheet 23 is adjacent to the button surface of the light guide plate 22. The light source 24 is disposed on the side of the incidence surface of the light guide plate 22. The light guide plate 22 may be a transparent substrate. A light beam emitted by the light source 24 is incident into the light guide plate 22 from the incidence surface thereof, and then leaves the light guide plate 22 from the top surface (light emitting side) before passing through the diffusion plate 25, the first brightness enhancement film 26, and the second brightness enhancement film 27. The brightness enhancement films 26 and 27 are used to control the emergence angle of light so that the light emitted by the light source 24 may be collected in the predetermined range of the viewing angle. As a result, the brightness of the display is increased. The diffusion plate 25 is used to optimize the viewing effect. Further, a stack of three optical films are needed to increase the quality of the conventional display 10 according to the conventional design.